The term “flexible electronics” refers to processes for assembling electronic circuits by making or otherwise providing electronic devices on such flexible plastic substrates as polyimides or certain transparent conductive polyester films, where the circuits can be screen printed on such substrates, or certain other substrates. Flexible electronic assemblies thus may be manufactured with many of the same components used for the preparation of rigid printed circuit boards, where being flexible allows these assemblies to conform to a desired shape, or to flex during their use. Also, flexible electronics can refer to various etching techniques for forming known thin silicon substrates. Flexible printed circuits (FPC), also known as flex circuits, can be prepared by photolithographic technology by, for example, laminating very thin copper strips in between two layers of a polyester polyethylene terephthalate (PET), about 0.05 millimeter thick, and where there is present a base material or substrate of, for example, a polyester, a polyimide, a polyethylene naphthalate, or a polyetherimide, and where a metal foil like copper is used as the conductive element from which the circuit paths are normally etched.
A number of disadvantages are associated with electronic devices, such as for example, they can be costly to fabricate, the layers that are present tend to separate thereby rendering the devices inoperable for their intended purposes causing, for example, some of the layers that contain exposed materials, or protrusions on their surfaces, to adversely affect the characteristics of the layers involved and disrupt the functions of these layers. Moreover, these devices can possess undesirable surface roughness primarily because of the migration of chemical substances, like oligomers, to the electronic device surface, such as a memory cell surface, which in turn degrades the optical and electrical performance of the devices. Many of the known memory devices are prepared by a stepwise sequence that decreases yields, increases cost, and results in unacceptable surface roughness.
There is a need for memory cells and memory devices, and compositions thereof that minimize, or substantially eliminate the disadvantages illustrated herein.
Also, there is a need for devices that contain layers that are free, or substantially free of separation.
There is also a need for compositions that bond the device layers below and above an adhesive layer.
Yet another need resides in providing devices and compositions thereof that possess acceptable surface roughness, and where the surface possesses smooth characteristics.
Additionally, there is a need for adhesive layers that have excellent chemical stability.
Moreover, needed are memory device adhesive layers that are thermally stable, and where the electrodes present, such as a silver electrode, retain their conductivity.
Also, there is a need for thermally cured planarization coatings that have adhesive properties, and which coatings can be permanently attached to substrates and electrodes present in a memory device.
Further, there is desired the preparation of devices that contain an adhesive coating generated by roll to roll processes.
Additionally, there is a need for thermally cured planarization adhesive coatings present on suitable flexible substrates, and which coatings can be applied to the flexible substrates, like polyesters, by roll to roll methods and result in smooth substrate surfaces.
These and other needs and advantages are achievable in embodiments with the processes and compositions disclosed herein.